5. Manage startup items
Some applications, on being installed, place stub or helper programs in your startup items without making it clear that they are doing so. Sometimes this is desirable, say if you always want iChat to open when you log in. But others, typically scanner- or printer-related applications, aren't always needed and can slow down the login process and hog CPU cycles unnecessarily.
Go to System Preferences > Accounts > Login items. Delete any you don't need. This rarely causes problems – if it does, put it back on the list.
6. Run only what you need
Running applications uses resources including CPU cycles, RAM and disk activity. If you're not using an application, quit it while you run others. Leaving programs open when they're not needed is a resource hog and, especially on older Macs, will slow you down.
Some programs can have problems with "memory leakage", meaning when loaded but idle, over time they will consume more and more RAM, eventually slowing you down. Use Activity Monitor located in the Utilities folder to see what resources each program is using.
7. Stay lean and mean
Keep a handle on what you install. Installing tons of programs and forgetting about them results not only in clutter and wasted space, but can also slow you down. Many programs place library files and startup items into the system, some of which must be loaded on startup whether you use the program or not.
Many come with an uninstaller, or you can use AppZapper to completely remove them. Over time, systems invariably get cluttered so if you are confident in your skills, periodically backing up and reinstalling OS X from scratch will keep it lean and mean.
8. Stay up to date
Each new version of OS X is faster than the last, and each point update – say from 10.5.3 to 10.5.4 – tends to improve speed and stability. The same goes for applications, so your software and drivers up to date using Software Update and the websites for non- Apple programs. Many apps have a check for updates option. Look at the minimum specs for your version of OS X. If your Mac is barely qualified to run 10.5, you'll have a smoother experience sticking with 10.4.11.
9. Install more memory
Having bought more RAM for your Mac, checking first that it is the correct type for your model, power down and disconnect all cables, especially the mains power. Touch a metal part of the casing to earth yourself. Open the Mac's RAM slot, the location of which will differ depending on the model, and carefully but firmly press the modules into place.
On G5s and Intel Macs, RAM sticks must be installed in pairs. Close up, reconnect the power and check System Profiler to see if it's working. If your Mac won't start up, check the modules are properly fitted.
10. Know your limits
Computer technology advances quickly, but so do the minimum system requirements of software. A seven year-old G4 is unlikely to be an ideal Mac to edit HD video on, for example. But older Macs are far from worthless and can be used as servers, internet and email machines, or even for hosting wireless shared iTunes libraries.
Pick up a cheap older Mac, fill it with RAM and big internal or external drives and a wireless card and administer it using Apple's Remote Desktop (£349, http://store.apple.com/uk). All this can be done quite cheaply.
11. Processor performance
On some older G4 and G5 systems, you can set the processor performance to Highest in System Preferences > Energy Saver. Automatic switches between the Highest and Reduced settings to optimise energy use.
12. Stripped down
A Mac with fewer or even no peripherals connected over USB or FireWire will run a little quicker than the same Mac with loads of printers and webcams plugged in.
13. Out and about
When running a laptop off its battery, switching off AirPort and Bluetooth will save power if you're not using them.
14. Multiple accounts
Try having one user account for things like games and internet, and another that's more fine-tuned and tweaked for heavier work.
15. Graphics card
On a tower Mac, even though you can't always remove the standard graphics card, you can add a new, faster one in a PCI slot and use that instead.
16. Backup schedule
Set your backup schedule so it doesn't start to grind away in the middle of your work. A Mac is designed to stay on, so you can set it for the middle of thie night.
17. Disk doctor
Perform a disk repair and use something like OnyX to regularly clear out caches, log files and temporary items to keep the system lean.
18. Static wallpaper
Using animated desktop backgrounds look great but they use up a lot of system resources unnecessarily, so avoid it if possible. A simple, static photo of a landscape or your family is just as pleasurable.
19. FireWire is faster
Despite theory seeming to suggest otherwise, FireWire is actually faster in practice than USB 2.0 for intensive applications like audio or video capture. Give it a try for yourself.
20. Stay organised
Believe it or not, folders with thousands of items in them take a lot longer to work with, as the Mac tries to calculate the sizes of the whole folder. Practise good file management.
First published in MacFormat Issue 200
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